Numerous types of heat transfer systems have been developed. Prior systems include vapor compression type heat pump systems which may be used for heating and/or cooling an interior area of a structure or water housed in a pool or other reservoir. Such prior systems have most often been powered electrically. Other systems have been powered by combustion processes such as the systems shown in U.S. Pat. Nos. 5,509,274; 5,313,874; 5,246,350; and 5,205,133.
In the development of combustion powered heat transfer systems advances are constantly sought. Increases in heat transfer capacity and energy efficiency are always desired. Other areas in which improvements in such systems are desirable include reliability, cost of equipment and cost of operation.
A limitation of some types of heat transfer systems that include heat pumps is that they are of limited effectiveness when outside temperatures are low. As a result persons desiring to heat a building with a heat pump system must also have an auxiliary heat source. Such alternative heat sources are conventionally either electric resistance heat or a gas fired heater. Due to the often relatively low cost of natural gas and the increases in efficiency that have been achieved in recent years with gas furnaces, many persons prefer to heat solely with natural gas where it is available. When air conditioning is desired, a separate vapor compression type system must be combined with the heating system to provide cooling during summer months. This results in an operator incurring higher costs for an electrically powered vapor compression air conditioning system and a gas fired heating system. The air conditioning system uses relatively more expensive electrical power which increases overall utility costs.
Thus there exists a need for a combustion powered cooling system that can operate using natural gas to cool a building, fluid or other item. There further exists a need for a combustion powered cooling system that has a higher capacity, is more energy efficient, is relatively low in cost and is more reliable than existing systems. There further exists a need for a combustion powered cooling system that may be readily modified and used as a heating device.